Acetazolamide

Abdelwahab Ward, BS Pharm, PharmD
CIDAMEX 250 MG, ACETAMEX...
MECHANISM OF ACTION ― Acetazolamide is a carbonic anhydrase inhibitor. That means this drug works to cause an accumulation of carbonic acid by preventing its breakdown. The result is lower blood pH (i.e., more acidic), given the increased carbonic acid, which has a reversible reaction into bicarbonate and a hydrogen ion.
  • Reduction of intra-ocular pressure in open-angle glaucoma, Reduction of intra-ocular pressure in secondary glaucoma, Reduction of intra-ocular pressure perioperatively in angle-closure glaucoma
      • By mouth using immediate-release medicines, or by intravenous injection, or by intramuscular injection For Adult: 0.25–1 g daily in divided doses, intramuscular injection preferably avoided because of alkalinity.
  • Glaucoma, By mouth using modified-release medicines. For Adult: 250–500 mg daily.
  • Epilepsy, By mouth using immediate-release medicines, or by intravenous injection, or by intramuscular injection. For Adult: 0.25–1 g daily in divided doses, intramuscular injection preferably avoided because of alkalinity.
  • Dose adjustment
      • Hepatic impairment: Manufacturer advises avoid.
      • Renal impairment: Avoid — risk of metabolic acidosis.
  • Adrenocortical insufficiency; hyperchloraemic acidosis; hypokalaemia; hyponatraemia; long-term administration in chronic angle-closure glaucoma
  • Cautions
      • Avoid extravasation at injection site (risk of necrosis); diabetes mellitus; elderly; impaired alveolar ventilation (risk of acidosis); long-term use; pulmonary obstruction (risk of acidosis); renal calculi
  • Common or very common: Hemorrhage; metabolic acidosis; nephrolithiasis; sensation abnormal
  • Uncommon: Bone marrow disorders; depression; dizziness; electrolyte imbalance; hearing impairment; hepatic disorders; leucopenia; nausea; renal colic; renal impairment; renal lesions; severe cutaneous adverse reactions (SCARs); skin reactions; thrombocytopenia; tinnitus; urinary tract discomfort; urine abnormalities; vomiting
  • Rare or very rare: Anaphylactic reaction; appetite disorder; confusion; diarrhea; fatigue; fever; flushing; headache; irritability; libido decreased; paralysis; photosensitivity reaction; seizure
  • Specific side-effects: Osteomalacia with oral use
  • Monitoring requirements: Monitor blood count and plasma electrolyte concentrations with prolonged use.
Abdelwahab Ward, BS Pharm, PharmD